Reproduction of published interatomic potentials

Hi if anyone can help me here that would be amazing.
I am as the first step of my research and learning GULP attempting to reproduce published interatomic potentials for La2CuO4. So far I’ve managed to get data on the unit cell, fractional coords and space group. However, I am not sure what to do next with any other lines of code and the keywords to use. I understand I can input buckingham potentials from a paper but does this not just avoid the point of trying to reproduce them.

The best thing to do is to go through the example files & substitute your system for that in the example.
Of course your supervisor should be able to provide guidance on what to do as well.